相关论文: Light Quark Masses
In the first part of the talk, I discussed results on the determination of the ratios of the light quark masses from large N_c chiral perturbation theory, to be described elsewhere. The following notes contain material from the second part…
We develop quenched chiral perturbation theory for vector mesons made of light quarks, in the limit where the vector meson masses are much larger than the pion mass. We use this theory to extract the leading nonanalytic dependence of the…
Consequences of the alternative mechanism of spontaneous breaking of chiral symmetry without formation of a large quark antiquark condensate is reviewed. Emphasis is put on the resulting picture of light quark masses.
We review some approaches to the quark-lepton mass problem. The ideas of mass-protection and approximate chiral flavour symmetries as a framework for resolving the mass hierarchy problem are presented. Dynamical calculations of the top…
I review the present state of our knowledge about the masses and weak mixing elements of the u, d, s quarks. This is the written version of lectures given in the 1993 Theoretical Advanced Study Institute (TASI).
An important tool for the analysis of results of numerical simulations of lattice QCD is chiral perturbation theory. In Wilson chiral perturbation theory the effects of the finite lattice spacing $a$ are taken into account. In recent years…
Low energy precision experiments provide significant tests of the laws of nature that can reveal physics beyond the Standard Model. A good theoretical understanding of the low energy properties of QCD is required for this purpose. The…
We study light (current) quark masses in framework of chiral constitutent quark model. In our calculation the current quark masses are defined uniquely, and all order effects of the light quark masses are considered. The results at energy…
The nontrivial topological structure of the QCD gauge vacuum generates a CP breaking term in the QCD Lagrangian. However, measurements of the neutron electric dipole moment have demonstrated that the term's coefficient is unnaturally small,…
Several topics concerning the light hadron spectrum are discussed. Flavor symmetry breaking effects and the problem of quenched chiral logarithm are examined with pion mass data for the Kogut-Susskind quark action, and light meson decay…
The mass splittings of the pseudoscalar and vector D and B light-heavy quark systems have been calculated using the method of QCD sum rules. Electromagnetic, quark mass, and nonperturbative QCD effects are all included. The results are in…
We make an attempt to describe the spectrum of masses of elementary particles, as it comes out empirically in six distinct scales. We argue for some rather well defined mass scales, like the electron mass: it seems to us that there is a…
Outline: 1. Introduction, 2. Confinement, chiral dynamics and light scalar mesons, 3. Chiral shielding of the \sigma(600), chiral constraints (the CGL band), the \sigma(600) and the f0(980) in \pi\pi->\pi\pi, \pi\pi->KKbar,…
In a series of three lectures, I review the theory and phenomenology of heavy quark masses and mixing angles and the status of their determination. In addition, I give an introduction to heavy quark symmetry, with the main emphasis on the…
By means of unitarized Chiral Perturbation Theory it is possible to obtain a remarkable description of meson-meson scattering amplitudes up to 1.2 GeV, and generate poles associated to scalar and vector resonances. Since Chiral Perturbation…
Chiral perturbation theory, the low energy effective theory of the strong interactions for the light pseudoscalar degrees of freedom, is based on effective Lagrangian techniques and is an expansion in the powers of the external momenta and…
Chiral symmetry and heavy quark symmetry constrain the interactions of mesons containing a single heavy quark with low-momentum pions. Chiral corrections to the Isgur-Wise function for $\bar B_s \rightarrow D_s^{(*)}$ versus $\bar B…
In this work, the mass of the strange quark is calculated from QCD sum rules for the divergence of the strangeness-changing vector current. The phenomenological scalar spectral function which enters the sum rule is determined from our…
The status of lattice determinations of quark masses is reviewed (with the exception of m_b). Attempts to extract the low-energy constants in the effective chiral Lagrangian are discussed, with special emphasis on those couplings which are…
This work is divided in two parts. In the first three sections we review the meson physics phenomenology, highlighting the history of the pseudoscalar multiplet mass spectra research. Then we propose a new approach for the mass mixing…